1. Field
The following description relates to methods and apparatuses for estimating a position distribution of radiation emission.
2. Description of Related Art
Medical imaging equipment that obtain images of a human body in order to diagnose a patient provide information necessary for disease diagnosis. Methods of medical imaging equipment which are currently being used or developed are largely divided into methods of obtaining an anatomical image or methods of obtaining a physiological image. Examples of imaging technology providing detailed anatomical images of the human body include magnetic resonance imaging (MRI) and computed tomography (CT). Both examples create 2-dimensional (2D) cross-sectional images of the human body or 3-dimensional (3D) images in high resolution using several 2D images. Such images provide precise positions and shapes of internal organs of the human body. An example of physiological imaging technology is positron emission tomography (PET). PET contributes to diagnosing by detecting abnormal metabolic processes from captured images of metabolic processes in the human body.
PET imaging includes using a special radiation tracer emitting positrons as a component participating in human metabolism. The tracer is typically introduced by intravenous injection or inhalation, and the tracer's position is typically traced by detecting two gamma rays of about 511 keV emitted in opposite directions when the positrons emitted from the tracer combine with electrons by an external device. A distribution change depending on a distribution shape and positions of the tracer over time is typically observed.